Upgrading from single stage to 3 stage VTEC

Placide · Postby **Placide** » February 18th, 2007, 7:53 pm

Guys I need some tech advice. I'm planning on upgrading from my single stage to a 3 stage VTEC. What do I need for this besides purchasing the new head?
The info I've obtained so far is :

"well basically you need the head alone but it looks like you want it for the extra hp and fuel economy .........in that case you would also need the ecu and the harness but you can get around that if you want to go for performance .......you can use your original ecu and run the first stage on all the time and use your ecu to controll the second stage "

Is this accurate? How does the 3 stage improve on fuel economy and HP? Can my ECU control the 3 stage effectively?

Doctor X · Postby **Doctor X** » February 18th, 2007, 9:27 pm

The clever Honda engineers saw that it is a logical step to merge the two implementations into one. This is in essence the 3-stage VTEC implementation. 3-stage VTEC is implemented on the D15B 1.5l SOHC engine in which the VTEC-E mechanism is combined with the power VTEC mechanism.

Many of us probably has laughed at the poor ignorant layman who said "I want power AND economy from my Honda". We know of course that power and economy are mutually exclusive implementations. Honda decided not to abide by this rule. Now, with 3-stage VTEC, we get BOTH power and economy !. Below 2500rpm and with gentle accelerator pressure, neither pin gets actuated. The engine operates in 12V mode with very good fuel combustion efficiency. When the right foot gets more urgent and/or above 2500rpm, the upper pin gets actuated. This is the VTEC-E mechanism at work and the engine effectively enters into the '2nd stage'. Now D15B 3-stage works in 16V mode (both intake valves works from the same mild cam-lobe).

Stage 2 operates from around 2500rpm to 6000rpm. When the rpm exceeds 6000rpm, the VTEC mechanism activates the wild cam-lobe pushing the engine into the '3rd stage', the power stage. Now the engine gives us the full benefit of its 130ps potential !

The 3-stage VTEC D15B engine is used on the current EK-series JDM Civic/ Civic Ferio VTi/Vi together with Honda's new Multimatic CVT transmission. Stage-1 12V or "lean-burn" operation mode is indicated to the driver by an LED on the dashboard. The 2500rpm cutover from lean-burn to normal 16V operation in fact varies according to load and driver requirements. With gentle driving, lean-burn can operate up to 3000rpm or higher. Stage-3 may not always be activated. The Multimatic transmission has a selector for Economy, Drive, and Sports mode. In Economy mode for eg, the ECU operates with a max rpm of around 4800rpm even at Wide-Open-Throttle positions.

hope this helps

Placide · Postby **Placide** » February 19th, 2007, 6:06 pm

Nice piece of info there Doctor X!

Doctor X · Postby **Doctor X** » February 19th, 2007, 9:56 pm

if you use your ecu and you run the first stage to the ignition then you wont be in the 12v mode .......you would be in 16valve all the time .......not going to get the fuel economy . would burn the same amout of gas as you do now

how do i know .........been there done that lol

...prob with changing the head might give a higher compression meaning more hp .....

waiting on kess vtec or redsupra to explain the rest of what i missed out ........ :mrgreen:

redsupra101 · Postby **redsupra101** » February 19th, 2007, 10:32 pm

^^ me? i eh kno nuttin bout civic boi. kes is d man

why do you want to go for the 3-stage if you already have a vtec motor?
if you're doing it strictly for the economy gains, then go strong.
head and ecu are all you really need. once you buy a head and ecu from the same year as your car.
if you buy a different year you may get a different OBD and may require an OBD adapter. (eg if u have a 99-00 civic and are buying a head off a 96-98 u may need a obd2b to obd2a adapter) or jus get it rewired to suit. your pick.

if its a power upgrade you're looking for, keep your money and buy other parts.

get a good air filter with some nice headers (Silvermike has some for sale) but u can keep your stock diameter piping and get a new barrel

then get an obd2 to obd1 adapter (only if ur 96-00/OBD2), obd1 manual ecu and give it to kes_vtec to have it chipped and tuned for your car.
he as successfully tuned semi-stock d15b's to shockingly straight flat torque 'curves'

kes_vtec · Postby **kes_vtec** » February 19th, 2007, 10:38 pm

i just got out the car, been play with the same sh*t all night...
this is what i have green wire is vtec, no two ways about it....
step one 12 volt from the battery, will not idle, will not run from 0 tuh 3000 rpm, after 3000 she is ready
with it off idles nice runs well, vtec runs well, boost feel good, but you can feel the car holding back something.
12 volt back in, foot in the gas to idle, after 3000 you see what was missing... vtec alot better, boost alot better.
so the plan wire the 1 stage vtec to one auto nos control control the will turn it one at 3200 till redline.
till then sleep

doctor X two switches for it yes... :mrgreen:

Placide · Postby **Placide** » February 20th, 2007, 11:28 am

Is it just me or is Kes talking a foreign language? :lol:

Slow your roll dude and break it down for someone who's "mechanically challenged" like myself. :roll:

If I buy the head and slap it on my 92 EG8 D15B (manual BTW) what else will I need to do? Can I count on you to tune this on completion?

redsupra101 · Postby **redsupra101** » February 20th, 2007, 2:48 pm

^^ dat eh so bad man.. jus read it u go figure it out
if u find dat hard to understand :lol:

well boy u ha plenty to learn yet :lol:

redsupra101 · Postby **redsupra101** » February 20th, 2007, 3:15 pm

Placide wrote:Is it just me or is Kes talking a foreign language? Slow your roll dude and break it down for someone who's "mechanically challenged" like myself.
If I buy the head and slap it on my 92 EG8 D15B (manual BTW) what else will I need to do? Can I count on you to tune this on completion?

sweet.. u shud already be obd1.. chip it!

dizzEK3h · Postby **dizzEK3h** » February 21st, 2007, 10:38 am

i would advise you against it,the only benifit of using the 3 stage vtec in for
fuel economy,the power is similar to the single stage. to make the swap work properly you will need the P2J ecu and a conversion harness obd1 to
obd 2a, also you cannot chip a obd2 ecu,there are no upgrade camshafts
for the 3-stage vtec head. so keep your vtec head ,upgrade with a stage 1
or 2 crower camshaft, use the 3 stage intake manifold and you should be
happy with this mod. but if you are interested in exchanging your head for
a 3-stage one,let me know, i have a spare one. 8-)

Ravers · Postby **Ravers** » April 18th, 2007, 3:58 am

I've changed the head of my d15b 99-00 civic to one with a 3 -stage Vtec. I need to get the correct harness...I need to convert from obd2b to obd2a.....(I got this from this post) what else do I need???
Who does this harness replacement / Vtec connection in the St. Augustine/Curepe area?
I need more performance .... so I need assistance with "chipping the ECU"..... do I need another ECU?

At present I am driving around with the VTEC uninstalled .... Does this do any damages?

X, dizz, redsupra..... Please help.

dizzEK3h · Postby **dizzEK3h** » April 18th, 2007, 9:10 am

you don,t have to worry about doing any damage to your engine,by running
it without the Vtec soleinoids hooked up, u just won,t get the performance.
You should try and get the correct ECU(manual/auto) depending on what
type of transmission you are using. also the harness for the CVT has more
wires/plugs than the one for the manual. obd2 ecu are,nt that easy to be
chipped as obd 1.

Doctor X · Postby **Doctor X** » April 18th, 2007, 9:50 am

no damages with driving around with vtec uninstalled.
as for the harness if you want i have one ........would help you install it if you wish or any electrician . pretty easy just plug in and plug out , took me a few hrs to do though . and the ecu well i also have 3 -stage Vtec ecu , once you install the harness and ecu you should be good to go as for chipping thats another great idea for boost later on :mrgreen:

Ravers · Postby **Ravers** » April 18th, 2007, 10:35 am

Doctor X ...PM me a contact no. I'm interested in your assistance and also for the VTEC ECU...
One more thought for you guys...

Its an automatic. D15b ....99-00 model Civic.

I don't know if there is any additional issues...

Streetwise Performance · Postby **Streetwise Performance** » April 18th, 2007, 11:39 am

Ravers wrote:I've changed the head of my d15b 99-00 civic to one with a 3 -stage Vtec. I need to get the correct harness...I need to convert from obd2b to obd2a.....(I got this from this post) what else do I need???
Who does this harness replacement / Vtec connection in the St. Augustine/Curepe area?
I need more performance .... so I need assistance with "chipping the ECU"..... do I need another ECU?

At present I am driving around with the VTEC uninstalled .... Does this do any damages?

X, dizz, redsupra..... Please help.

ok, you are saying you swapped d15b head for 3-stage vtec head. You must use the ecu from the head you put in, or else the swap is useless, things will not work.

I can test an obd-1 ecu in your car, but you will have to get Obd2-b to obd-1 conversion harness.